Aromatase belongs to the cytochrome p450 enzyme family. Aromatase is the key enzyme in the estrogen biosynthesis. It converts the male sex hormones (androgens) into the female ones (estrogens). The latter are growth factors for a plurality of tumors, particularly those of ovaries, endometrium and breast.
For treating the above tumors, it is tried to inhibit the estrogen biosynthesis. Aromatase inhibitors are often used for this purpose. However, they have not shown satisfactory results by now, particularly they are lacking specificity.
Therefore, it is the object of the present invention to provide a preparation by which aromatase can be inhibited specifically.
According to the invention this is achieved by providing an antisense oligonucleotide which prevents the expression of aromatase by attachment to aromatase DNA and/or mRNA. The expression "antisense" is generally known and refers to a complementarily of the oligonucleotide sequence to the region of aromatase DNA and/or mRNA.